In an experiment, respondents were given two scenarios: How much were they willing to pay for

• a 24-piece luxury dinner set in good condition
• a 40-piece dinnerware set, where some items were broken.

The respondents were willing to spend twice as much for the 24-piece set even though the 40-piece set still had more pieces.

This effect is known as the dilution bias, where the broken items dilute the overall perceived value. This cognitive effect has important implications for our ability to be heard and listened to when we speak.

Far too often, people speak up but fail to influence. Their message was sound, but their delivery was faulty.

Our minds use two types of information:

• diagnostic (relevant information) and
• nondiagnostic (irrelevant or inconsequential information).

When the two categories of information are mixed, dilution occurs.

When you introduce irrelevant or weak arguments, you will reduce the importance of your overall argument.